A MOTHER who drowned her four-year-old daughter after attending the birth of her partner's baby to another woman was jailed for five-and-a-half years today.

Rachel Cowley, 43, walked out of a Scottish hospital with her daughter Isabelle following the birth and drowned her in a stream nearby.

She left her daughter's body in the water, covered in leaves and vegetation.

The killing happened shortly after Cowley cut the newborn baby's umbilical cord at the hospital on February 22.

The High Court in Edinburgh heard today that Cowley, who was suffering from a personality disorder at the time, felt her world had "collapsed" following the birth of the baby.

Cowley was initially charged with murder, but prosecutors accepted her plea to the lesser charge of culpable homicide on the grounds of diminished responsibility.

At the court today, Cowley was given a 10-year extended sentence, meaning she will be supervised for a further four-and-a-half years following her release on licence from the jail term. The court was told that she plans to move to Ireland after she is released as she will have support from family members here.

Judge Lord Bannatyne told her: "What happened on the day of this incident was a dreadful tragedy, in which your daughter was deprived at such an early age of her life."

He added: "All of the family members have been devastated by the enormous loss they have sustained resulting from the death of Isabelle."

The court heard that Cowley, who also has a young son, lived an "alternative lifestyle".

At the time, Cowley, of Shenval, Glenurquhart, south of Inverness, was living with her partner, Chris Everitt - Isabelle's father - and another woman, Nicola Charles, 26.

Advocate depute Alex Prentice QC told the court in July that before the birth, Cowley, Mr Everitt and Ms Charles "entered into a full sexual relationship with each other".

However, Cowley appeared "broken" and "confused" after discovering Ms Charles was pregnant and asked a friend: "What am I going to do?"

In February she went to Raigmore Hospital, Inverness with Mr Everitt, 36, to help with the birth of Ms Charles's child.

During the process she became increasingly quiet and fell into a "trance-like state" for around 20 minutes before cutting the baby's umbilical cord.

At about 7pm that day, Cowley left the ward with Isabelle and was seen on CCTV walking in the hospital grounds.

Mr Prentice said: "After these sightings the accused drowned her daughter by holding her head under the water in the burn within the grounds of Raigmore Hospital.

"She placed leaves and vegetation on the child's body in an effort to conceal the body whilst it was left in the burn."

When she did not return, Mr Everitt reported them missing and police began searching the grounds.

Officers found the child's body shortly after 3am the following day.

First offender Cowley later told a police doctor: "I haven't been feeling very well and I think I did something to my little girl. I am very confused in my head, way confused.

"I thought I had to do it and now I feel really bad. I don't think anyone asked me to do it. I felt confused in my brain."

Murray Macara QC, defending, said it was a "difficult, anxious and tragic" case.

He said Cowley was a vulnerable person who found the birth of the child "made her domestic situation untenable" and her world "collapsed".

"Her role in this relationship was clearly undermined when Nicola Charles's baby was born," he added.

The lawyer said it was possible Cowley had also intended to take her own life.

He said: "It's hard to imagine a case more difficult, anxious and tragic than a mother killing her daughter."

In passing sentence, Lord Bannatyne said it was a serious charge but there were a number of mitigating factors in the case.

He said she had previously been of good character and had no other convictions.

He added that before the incident she had been a "loving and caring" parent towards Isabelle and was suffering from a personality disorder at the time of the offence.

The court heard Cowley's long-term plan is to move to Ireland, where she would have the support of family members.